Physical retail is the last big black box in marketing measurement. Over 80% of retail sales still happen inside stores, yet in-store accounts for roughly 3.3% of US non-Amazon retail media spend, according to eMarketer. That gap isn't about demand — it's about trust in the numbers. The IAB in-store retail media measurement standards exist to close it. This article breaks down what they actually measure, what they deliberately leave open, and how to use them when a retail media network puts a proposal in front of you.
IAB In-Store Retail Media Measurement Standards: What They Are and Why They Exist Now
Two documents matter here. The IAB/MRC Retail Media Measurement Guidelines, published January 2024, were the first buy-side and sell-side framework to explicitly cover in-store retail media. Then on 3 December 2024, IAB and IAB Europe released the final In-Store Retail Media Definitions and Measurement Standards, following a two-month public feedback window.
These weren't written in a vacuum. The January 2024 working group included Walmart Connect, Grocery TV, GroupM, Publicis Groupe, P&G and Unilever. The December 2024 standards were developed with Ahold Delhaize, Douglas Marketing Solutions, Kingfisher, MediaMarkt and Schwarz Media — retailers and agencies who actually spend and earn this money. That mix is why the frameworks carry weight.
The Five Store Zones the IAB In-Store Retail Media Measurement Standards Recognize
Five zones. That's the first structural decision the standards make: exterior, entrance, checkout, aisles, and other. Shopper behavior changes sharply depending on where someone stands, which means a single undifferentiated "impression" count is analytically useless for anyone trying to connect placement to purchase behavior.
Zone tells you the realistic chance a shopper has to engage with a screen — and that should shape where you put budget and how long your creative runs. A 30-second spot makes sense where people wait. It's wasted where they're moving past in seconds.
Map the zones to intent and the picture gets clearer:
- Entrance zones capture discovery — shoppers deciding what today's trip is about.
- Aisle zones capture consideration — the moment of comparing options on shelf.
- Checkout zones capture last-mile conversion — the impulse grab and the reminder.
Each maps to a different objective. Treating them as one pool of impressions throws away the most useful thing zone data gives you.
The Four-Level Impression Hierarchy: From "Ad Played" to "Likelihood to See"
Four impression types. Each carries a different level of audience evidence, and the point is to let you compare like-for-like across networks instead of taking one vendor's "impression" at face value against another's. Most networks today report at the lowest levels of this hierarchy. Knowing which level you're buying is the difference between accountability and guesswork.
Level 1 and Level 2: Ad Play and Gross Impressions — the Baseline, Not the Goal
- Ad play (Level 1): the player logged that the creative ran. Zero audience signal. It's the equivalent of a server logging an ad call with no viewability data attached.
- Gross impression (Level 2): people present in the store zone while the ad played. Footfall-based. It says nothing about whether anyone was near the screen, at the right angle, or paying attention.
Watch for this: a network quoting "millions of impressions" pulled from footfall counts is reporting gross impressions — not audience-validated ones. Ask which level you're actually purchasing before you sign anything.
Level 3 and Level 4: Opportunity to See and Likelihood to See — Where Audience Measurement Begins
- Opportunity to See (OTS, Level 3): people positioned such that they could have seen the screen. It accounts for proximity and screen angle — but not confirmed attention.
- Likelihood to See (LTS, Level 4): a modeled estimate of how many people probably looked. This is the standard's current ceiling for audience-based buying.
The standard is refreshingly honest about its own limits. In-store viewability, it states, represents "an opportunity-to-see, rather than confirmation that someone has seen the ad." It also warns that digital viewability thresholds — 50% of pixels visible for 1 to 2 seconds — may not translate correctly to large-format in-store screens, pending further study.
LTS is still a model. Think of it as the estimated reach you'd get from an out-of-home billboard, not the confirmed view data you're used to from digital display. For anyone trying to prove that a store display drove traffic rather than the weather, that distinction is the whole game.
What the IAB In-Store Retail Media Measurement Standards Don't Yet Solve
Confirmed viewing — proof that a specific person looked at the screen while your creative played — is still an open gap. The hierarchy stops at "probably looked," and that ceiling hasn't moved.
Scope has limits too. The December 2024 standards cover digital screens, audio and connected shopping formats. Print and static placements were deferred. If a network bundles static signage into its numbers, that portion sits outside the framework entirely.
The commercial pressure behind this gap is real. IAB Europe's Attitudes to Retail Media 2025 study — roughly 180 senior respondents across 31 markets — found that 53% of buyers name lack of standardization as the primary barrier to investment, with 51% citing network fragmentation. Buyers prioritize transparency (82%), performance (76%), and measurement options (75%). ROAS is the most demanded metric, cited by 88%.
That's the tension. The current standards can't yet deliver verified ROAS attribution at the impression level. Buyers want confirmed performance; the framework tops out at a model of probable views.
Sensor-based measurement points beyond that ceiling. Pygmalios ScreenIQ calls it a verified view: presence, plus facing the screen, plus dwell time while the creative actually plays — reported per screen, per daypart, per creative. It's not standardized yet, but it's where the market is heading after LTS. The practical difference matters more than the terminology: LTS says "we estimate someone probably saw it"; a verified view says "here is the count of people physically oriented toward the screen while your creative ran." One is a defensible model. The other is a countable event.
How to Use the Standards When Evaluating a Retail Media Network
Start with a fact that trips up a lot of buyers: the standards are voluntary and method-agnostic. No certification body audits against them. The only accurate claim a network can make is "aligned with the IAB and IAB Europe in-store standards." Anyone selling you "IAB-compliant" or "IAB-certified" inventory is stretching the truth — those certifications don't exist.
The stakes justify the scrutiny. US in-store retail media is forecast to grow from $370M in 2024 to $1.06B by 2028, per eMarketer — a 45.5% growth rate in 2025 alone, against 20.2% for retail media overall. Networks that can genuinely demonstrate standards alignment will pull a disproportionate share of that budget. Your questions decide who earns yours.
Three Questions to Ask Any Retail Media Network Before You Buy
- Which impression level are you selling? Make them disclose whether quoted impressions are gross (footfall-based) or OTS/LTS (audience-positioned). Then ask for the methodology behind the number, not just the number.
- Which store zones are included, and what's the dwell time data per zone? Zone-level dwell data is the foundation of any real path-to-purchase analysis. A network that can't provide it can't help you optimize where creative goes.
- Can you report at the creative and daypart level, not just campaign totals? Granular reporting is the floor for connecting in-store media to the performance loop you already run in digital. Without it, the black box stays shut.
One caveat worth carrying into the conversation: static and print placements fall outside the current standards. If a network folds them into a package, ask for separate evaluation criteria for that portion.
What Good Reporting Actually Looks Like Under the IAB In-Store Retail Media Measurement Standards
Beyond knowing what to ask, you need to recognize a credible answer when you see one. A standards-aligned campaign report should give you:
- A breakdown by all five zones — exterior, entrance, checkout, aisles, other.
- Each impression metric clearly labeled with its level — OTS or LTS, not just a raw number.
- Dwell time per zone, so placement decisions have a factual basis rather than a guess.
- Creative-level and daypart-level data wherever sensor infrastructure supports it.
Treat the standards as a floor, not a ceiling. They give buyers and sellers a shared vocabulary — genuinely new, and genuinely useful. But the brands that win in-store retail media will be the ones pushing networks past modeled LTS toward sensor-confirmed audience data.
The bigger prize is an omnichannel one. Standardized in-store measurement makes it possible to compare an in-store impression to a digital impression on the same basis. Get that right, and the store stops being a black box and starts being a channel you can plan against — the same way you already plan search, social, and display.
Sources
- IAB — In-Store Retail Media Definitions and Measurement Standards — the five zones, impression hierarchy, and scope of digital, audio and connected formats.
- IAB/MRC Retail Media Measurement Guidelines (January 2024) — the first buy-side/sell-side framework covering in-store retail media.
- IAB Europe — In-Store Retail Media Standards release (3 December 2024) — final standards and contributing retailers.
- IAB Europe — Attitudes to Retail Media 2025 — standardization barriers, transparency and ROAS demand across 31 markets.
- eMarketer — In-store retail media forecasts (2024–2028) — spend growth figures and the in-store execution gap.